A thermochemical sensing transducer is known detecting the presence and concentration of various gases in the air such as air including CH.sub.3 or Hydrogen. The known sensing transducer of prior arts provides a higher measuring accuracy due to the layer of a catalyst (platinum, palladium, or metal oxides) applied to the external surface of the sensing element, and an extended range of gases monitored which is due to the fact the sensing elements are made of different materials, have different dimensions, and make use of different catalysts. Two silicon stages are installed independently on the same substrate for two constructionally similar sensing elements (save the aforementioned basic differences). An insulating nitride layer 400 mm thick is applied to the silicon membrane of the stage. A double-meander heater is established at the center of the sensing element, said heater being made of silicon or nickel and having aluminium electric leads to the sensing element periphery. A thermocouple consisting of two meanders connected in opposition and made of different materials is applied to the heater in perpendicular with the axis thereof. A catalyst layer is applied from above, which may be coated with a protective gas-permeable layer. The aforecited sensing transducer is capable of measuring concentration variations with temperature (DE, A, 4,008,150).
However, the aforementioned construction is sophisticated and inadequately technologically manufacturable.
A structure for the gas analyzer carrier is known from prior arts, said structure enabling to obtain a mechanically strong construction of analyzers for such gases as SO.sub.2, H.sub.2 S, and benzene suitable for the large-scale production. The construction of said structure appears as a square of 6.times.6 mm inside which another square of 2.times.2 mm is placed, both squares being interconnected with jumpers along the four diagonals common to both squares. The central square and partly two opposite jumpers are coated with a layer of platinum serving as a heater. The central square-shaped platinum coating is shaped as a spiral. The resultant resistor is coated with an insulating layer. Two electrodes made of platinum or gold are applied to the opposite sides of the central square, two metal strip electrodes directed along the free substrate jumpers being connected to said platinum or gold electrodes. A gas-sensitive film is applied to the central square between the electrodes (FR, A, 2,625,561).
However, the construction discussed above is sophisticated difficult to assemble, has no adequate selectivity due to an insufficient heat insulation of the central substrate portion, and is possessed of inadequate manufacturability.